THE SEMANTIC WEB: CONCEPTS AND TECHNOLOGIES
C O N T E N TS CHAPTER WHAT IS THE SEMANTIC WEB? WHY DO WE NEED THE SEMANTIC WEB? INFORMATION OVERLOAD STOVEPIPE SYSTEMS POOR CONTENT AGGREGATION HOW DOES XML FIT INTO THE SEMANTIC WEB? HOW DO WEB SERVICES FIT INTO THE SEMANTIC WEB? WHAT’S AFTER WEB SERVICES? WHAT DO THE SKEPTICS SAY ABOUT THE SEMANTIC WEB? WHY THE SKEPTICS ARE WRONG! SUMMARY CHAPTER THE BUSINESS CASE FOR THE SEMANTIC WEB WHAT IS THE SEMANTIC WEB GOOD FOR? DECISION SUPPORT BUSINESS DEVELOPMENT INFORMATION SHARING AND KNOWLEDGE DISCOVERY ADMINISTRATION AND AUTOMATION IS THE TECHNOLOGY FOR THE SEMANTIC WEB “THERE YET”? UNDERSTANDING XML AND ITS IMPACT ON THE ENTERPRISE WHY IS XML A SUCCESS? WHAT IS XML? WHY SHOULD DOCUMENTS BE WELL-FORMED AND VALID? WHAT IS XML SCHEMA? WHAT DO SCHEMAS LOOK LIKE? IS VALIDATION WORTH THE TROUBLE? WHAT ARE XML NAMESPACES? WHAT IS THE DOCUMENT OBJECT MODEL (DOM)? IMPACT OF XML ON ENTERPRISE IT WHY META DATA IS NOT ENOUGH SEMANTIC LEVELS RULES AND LOGIC INFERENCE ENGINES UNDERSTANDING WEB SERVICES WHAT ARE WEB SERVICES? WHY USE WEB SERVICES? DO WEB SERVICES SOLVE REAL PROBLEMS? IS THERE REALLY A FUTURE FOR WEB SERVICES? HOW CAN I USE WEB SERVICES? UNDERSTANDING THE BASICS OF WEB SERVICES WHAT IS SOAP? HOW TO DESCRIBE BASIC WEB SERVICES HOW TO DISCOVER WEB SERVICES WHAT IS UDDI? WHAT ARE EBXML REGISTRIES? ORCHESTRATING WEB SERVICES A SIMPLE EXAMPLE ORCHESTRATION PRODUCTS AND TECHNOLOGIES SECURING WEB SERVICES XML SIGNATURE XML ENCRYPTION XKMS SAML XACML WS-SECURITY LIBERTY ALLIANCE PROJECT WHERE SECURITY IS TODAY WHAT’S NEXT FOR WEB SERVICES? GRID-ENABLED WEB SERVICES A SEMANTIC WEB OF WEB SERVICES UNDERSTANDING THE RESOURCE DESCRIPTION FRAMEWORK WHAT IS RDF? CAPTURING KNOWLEDGE WITH RDF OTHER RDF FEATURES WHY IS RDF NOT IN THE MAINSTREAM? WHAT IS RDF SCHEMA? WHAT IS NONCONTEXTUAL MODELING? UNDERSTANDING THE REST OF THE ALPHABET SOUP XPATH THE STYLE SHEET FAMILY: XSL, XSLT, AND XSLFO XQUERY XLINK XPOINTER XINCLUDE XML BASE XHTML XFORMS SVG UNDERSTANDING TAXONOMIES OVERVIEW OF TAXONOMIES WHY USE TAXONOMIES? DEFINING THE ONTOLOGY SPECTRUM TAXONOMY THESAURUS LOGICAL THEORY ONTOLOGY TOPIC MAPS TOPIC MAPS STANDARDS TOPIC MAPS CONCEPTS TOPIC OCCURRENCE ASSOCIATION SUBJECT DESCRIPTOR SCOPE TOPIC MAPS VERSUS RDF RDF REVISITED COMPARING TOPIC MAPS AND RDF UNDERSTANDING ONTOLOGIES OVERVIEW OF ONTOLOGIES ONTOLOGY EXAMPLE ONTOLOGY DEFINITIONS SYNTAX, STRUCTURE, SEMANTICS, AND PRAGMATICS SYNTAX STRUCTURE SEMANTICS PRAGMATICS EXPRESSING ONTOLOGIES LOGICALLY TERM VERSUS CONCEPT: THESAURUS VERSUS ONTOLOGY IMPORTANT SEMANTIC DISTINCTIONS EXTENSION AND INTENSION LEVELS OF REPRESENTATION ONTOLOGY AND SEMANTIC MAPPING PROBLEM KNOWLEDGE REPRESENTATION: LANGUAGES, FORMALISMS, LOGICS SEMANTIC NETWORKS, FRAME-BASED KR, AND DESCRIPTION LOGICS LOGIC AND LOGICS PROPOSITIONAL LOGIC FIRST-ORDER PREDICATE LOGIC ONTOLOGIES TODAY ONTOLOGY TOOLS LEVELS OF ONTOLOGIES: REVISITED EMERGING SEMANTIC WEB ONTOLOGY LANGUAGES DAML+OIL OWL CRAFTING YOUR COMPANY’S ROADMAP TO THE SEMANTIC WEB THE TYPICAL ORGANIZATION: OVERWHELMED WITH INFORMATION THE KNOWLEDGE-CENTRIC ORGANIZATION: WHERE WE NEED TO BE DISCOVERY AND PRODUCTION SEARCH AND RETRIEVAL APPLICATION OF RESULTS HOW DO WE GET THERE? PREPARE FOR CHANGE BEGIN LEARNING CREATE YOUR ORGANIZATION’S STRATEGY MOVE OUT! T H E S E M A N T I C WE B XII INSTALLING CUSTOM CONTROLS WHAT IS THE SEMANTIC WEB? “THE FIRST STEP IS PUTTING DATA ON THE WEB IN A FORM THAT MACHINES CAN NATURALLY UNDERSTAND, OR CONVERTING IT TO THAT FORM THIS CREATES WHAT I CALL A SEMANTIC WEB—A WEB OF DATA THAT CAN BE PROCESSED DIRECTLY OR INDIRECTLY BY MACHINES ” —TIM BERNERS-LEE, WEAVING THE WEB, HARPER SAN FRANCISCO, C HAPTE R WE SEE RELATIONS BETWEEN INFORMATION ITEMS LIKE “INCLUDES,” “DESCRIBES,” AND “WROTE ” UNFORTUNATELY, THESE RELATIONSHIPS BETWEEN RESOURCES ARE NOT CUR- RENTLY CAPTURED ON THE WEB THE TECHNOLOGY TO CAPTURE SUCH RELATIONSHIPS IS CALLED THE RESOURCE DESCRIPTION FRAMEWORK (RDF), DESCRIBED IN CHAPTER 5 THE KEY POINT TO UNDERSTAND ABOUT FIGURE 1 1 IS THAT THE ORIGINAL VISION ENCOM- PASSED ADDITIONAL META DATA ABOVE AND BEYOND WHAT IS CURRENTLY IN THE WEB THIS ADDITIONAL META DATA IS NEEDED FOR MACHINES TO BE ABLE TO PROCESS INFOR- MATION ON THE WEB